Audio phase issues with DVX100 at DVinfo.net

George Odell · July 11th, 2005, 07:55 AM

Has anyone experienced any audio phase issues between using the on-camera mic on one channel and the external line input on the other with this camera?

Bob Costa · July 11th, 2005, 08:28 AM

I can't help with that, since I have a DVX100a. You do know that the 100 has a 2 frame delay between picture and audio that has to be corrected in post, right??

George Odell · July 11th, 2005, 11:31 AM

Used this camera this weekend for the first time.

On-camera mic set for channel B and my Cooper Sound mixer into line-in for channel A. There appeared to be a phase issue (channels not completely in phase) with this setup.

Since I had to leave the camera behind I had no chance to bench test my theory.

Yes, I am also aware of the delay, which made monitoring a real pain. The reason for this is what?

Jim McQuaid · July 28th, 2005, 10:58 AM

The two frame delay is a function of the frame processing overhead, especially or mostly in 24p modes. It's not a synch problem, just an overall delay in what is written to tape.

I'm under the impression that "audio phase" problems are primarily related to mike placements, with the possibility that sound waves arriving at one are out of phase to those arriving at a second mike, with the result that a stereo output can appear to minimize or cancel out the sound. I should not be related to which input is used on the camera.

July 11th, 2005, 07:55 AM	#1
George Odell Major Player Join Date: Jun 2005 Posts: 270	Audio phase issues with DVX100 Has anyone experienced any audio phase issues between using the on-camera mic on one channel and the external line input on the other with this camera? __________________ "the difference between an amateur photographer and a professional is the amateur shows you all his pictures"

July 11th, 2005, 08:28 AM	#2
Bob Costa Major Player Join Date: Nov 2004 Location: Venice, FL Posts: 850	I can't help with that, since I have a DVX100a. You do know that the 100 has a 2 frame delay between picture and audio that has to be corrected in post, right?? __________________ You are either growing or dying.

July 11th, 2005, 11:31 AM	#3
George Odell Major Player Join Date: Jun 2005 Posts: 270	Used this camera this weekend for the first time. On-camera mic set for channel B and my Cooper Sound mixer into line-in for channel A. There appeared to be a phase issue (channels not completely in phase) with this setup. Since I had to leave the camera behind I had no chance to bench test my theory. Yes, I am also aware of the delay, which made monitoring a real pain. The reason for this is what? __________________ "the difference between an amateur photographer and a professional is the amateur shows you all his pictures"

July 28th, 2005, 10:58 AM	#4
Jim McQuaid Regular Crew Join Date: Nov 2003 Location: Durham, North Carolina Posts: 61	audio phase, delay and such The two frame delay is a function of the frame processing overhead, especially or mostly in 24p modes. It's not a synch problem, just an overall delay in what is written to tape. I'm under the impression that "audio phase" problems are primarily related to mike placements, with the possibility that sound waves arriving at one are out of phase to those arriving at a second mike, with the result that a stereo output can appear to minimize or cancel out the sound. I should not be related to which input is used on the camera.